This invention relates, in general, to electronics, and more particularly, to methods of assembling components onto a circuit board and electronic components thereof.
In the electronics industry, many different types of components, including semiconductor devices and heat sinks, are assembled or mounted onto circuit boards to create electronic components. Some semiconductor devices require discrete, external heat sinks to efficiently dissipate heat from the semiconductor devices. These heat sinks are mounted onto the circuit board over the semiconductor devices.
Ball Grid Array (BGA) devices and Quad Flat Pack (QFP) devices are two examples of semiconductor devices that mount directly onto the circuit boards. Some of the BGA and QFP devices do not entirely encapsulate the semiconductor chip of the device. Instead, the back side of the semiconductor chip is exposed to more efficiently dissipate heat from the semiconductor chip. However, these exposed-die BGA and QFP devices are not compatible with the discrete, external heat sinks.
Furthermore, heat sink anchors are mounted onto the circuit board to couple the heat sinks to the circuit board. However, these anchors must be manually mounted onto the circuit board. Therefore, the anchors are not compatible with a high speed, high volume assembly process. Additionally, the heat sink anchors protrude through the circuit board and extend at least 0.25 centimeters beyond the back side of the circuit board. This large protrusion renders the resulting electronic component unusable in many applications having strict height limitations on the back side of the circuit boards.
Moreover, as the semiconductor devices increase in speed, the semiconductor devices radiate higher frequency emissions. Industry regulations require these high frequency emissions to be shielded from adjacent electronic components.
Accordingly, a need exists for a method of assembling components onto a circuit board and an electronic component thereof where the heat sink of the electronic component is compatible with exposed-die semiconductor devices, where the heat sink anchors are compatible with a high speed, high volume assembly process, where the heat sink anchors do not violate the height limitations of certain applications, and where the radiated high frequency emissions from the semiconductor devices are shielded from neighboring components.